Special enough to have letters after its name

Michael Jackson celebrates the spring with a pint of mysteriously titled Original A K from the modest Hertfordshire brewery, McMullen's

If Spring appears this weekend, celebrate it with a pint (if it does not, commiserate in a similar manner). And for this special occasion, avoid anything as ordinary as a supposedly quenching lager or a mass-market ale. Look for something wonderful instead. Such beers are not all strong. Quality concerns flavour, not strength. British brewers have a unique genius for producing low-strength beers that blossom with flavour: a light touch of sweet, clean barley malt; an almost stinging freshness of hops; a tangy, fruity acidity of yeast.

The gentleness of these beers seems to hush their producers. In London we hear too little of Fuller's Chiswick Bitter (a mere 3.5 per cent alcohol); in Manchester not enough is seen of Robinson's Best Mild (3.3 per cent); Edinburgh would undoubtedly welcome a wider availability of its Caledonian Sixty Shilling (at 3.2 per cent alcohol it costs rather less than its name).

If awards for modesty were not a contradiction, the gold medal would surely go to the brew mysteriously named Original A K (at 3.8 per cent), and its producer McMullen's (never heard of it? Who has?).

Despite its reticence, this beer is enjoyed by trendies in Covent Garden at the Nag's Head, and the nearby Spice of Life, Cambridge Circus. and across suburban north London to countryish Hertford, where it is produced. McMullens, which has several other brews, makes A K only once a week in winter. In summer, which for its purposes starts this month, it switches to twice-weekly production. That is excuse enough to name it my Beer of the Month.

In other areas balance may be unexciting, but in drinks it is teasingly interesting, as first one flavour and then another comes to the fore.

McMullen's Original A K is one of the best-balanced beers I have ever tasted. In other areas balance may be unexciting, but in drinks it is teasingly interesting, as first one flavour and then another comes to the fore. At first I decided A K was a malty beer. Then I was not sure - perhaps the hoppiness was more evident. Finally I decided it was refreshingly acidic. Or was it? Perhaps I needed another pint to establish its salient quality.

Could it be the water, flowing from the Chilterns through chalk to wells beneath the brewery? Chalky waters give firmness of body and depth of flavour to ales and McMullens even adds a little gypsum. Barley from East Anglia is mashed in Hertfordshire, an old centre of that alchemy. In addition to pale ale malt. a dash of the type described by brewers as chocolate is added. The hops of the variety Goldings (earthy, faintly oily, aromatic) come from Kent.

The yeast culture, in the hands of McMullens for many years. originally came from a London brewery. McMullens feels this culture unmasks malty flavours, but I think it brings dryness. In the interaction of its elements, brewing still holds mysteries.

The stainless steel brewhouse is only seven or eight years old, but an earlier model from 1891 with some copper vessels that were bought second-hand at the time, is still used. All the ale is fermented in copper-lined oak vessels.

The brewery's manager and foreman are father and son. On the manager's desk, the in-tray is the home of Moggy, the brewery's black cat. McMullen's has no horses, but it has kept a dray that looks as though it was unhooked from Wagon Train, and a steam-powered lorry.

"We've never been high-profile," murmurs Fergus McMullen the sales director. "We don't like to show off. I suppose we ought to change in this competitive world."

"We've never been high-profile," murmurs Fergus McMullen the sales director. "We don't like to show off. I suppose we ought to change in this competitive world." Dennis Routledge, the company's veteran public relations man, with side-whiskers, bow-tie, silk waistcoat and watch-chain, nods sympathetically.

McMullen's gives a drink to guests in a pargeted cottage dating from the 1600s. Next door is a former maltings, now a seed store. The site seems likely to have been a farm with its own brewhouse. The family, distantly from Ireland, trace their history from 1796. They founded the present brewery in 1827, and A K seems to have been made since 1832.

The main brewery buildings date from 1891. The rooftop clock, installed at that time, previously decorated London's Wormwood Scrubs prison. "One of my forebears must have thought it a bargain," explains Fergus McMullen. There are four McMullens in the company, which is one of the principal local employers. Its various premises, present and past - and its pubs - are all over the town.

A couple of years ago, through its pubs, McMullen's asked its customers if they could shed any light on the origins of the name A K. There were answers aplenty, but none that made much sense. "McMullen no nearer to solving A K mystery," said the pub-trade paper, The Morning Advertiser, gravely. The company genuinely does not know.

The antiquity of the beer rules out the popular theory that it was originally named Asquith's Knockout, after the Prime Minister who tripled tax on stronger brews in 1914.

There were once more than a dozen beers called A K in Hertfordshire and a good few in other parts of the country, as far away as Burton and Bristol. The term seems always to have indicated an ale of modest strength, but what do the initials mean? The antiquity of the beer rules out the popular theory that it was originally named Asquith's Knockout, after the Prime Minister who tripled tax on stronger brews in 1914.

Another story has a famous brewer called Arthur King. "AS much a myth as King Arthur." sighs Martyn Cornell, a beer historian, in a 2,000-word investigation in The Journal of the Brewery History Society.

Low-strength brews are not laid-down, so the "K" could not have indicated a "Keeping Beer". Perhaps it was a corrupted "X"? In the days before widespread literacy, this mark (or a triangle or diamond) was branded on casks in ascending numbers as an indication of strength.

Mr Cornell thinks the "K" may have been derived in the 1400s from an old flemish word, kuyte, meaning a small beer. This is not as far-fetched as it sounds. British brewers still use technical terms originating from the influence of the flemish brewers. Better still, McMullen's head brewer has the surname Skipper. His family name is, he agrees, of flemish origin.